from django.core.paginator import Paginator, EmptyPage, PageNotAnInteger
from django.shortcuts import render,get_object_or_404
from django.core.mail import send_mail
from .models import Post
from .forms import EmailPostForm, CommentForm
from taggit.models import Tag
from django.db.models import Count
from django.contrib.postgres.search import SearchVector
from .forms import EmailPostForm, CommentForm, SearchForm

def post_list(request,tag_slug=None): 
    posts = Post.published.all()
    tag = None
    if tag_slug:
        tag = get_object_or_404(Tag, slug=tag_slug)
        posts = posts.filter(tags=tag)
    paginator = Paginator(posts, 3)
    page = request.GET.get('page')
    try:

        posts = paginator.page(page)
    except PageNotAnInteger:
        posts = paginator.page(1)
    except EmptyPage:
        posts = paginator.page(paginator.num_pages)
    return render(request, 'blog/post/list.html',{'posts': posts,'page':page,'tag':tag})
    
def post_detail(request, year, month, day, post):
    post = get_object_or_404(Post, slug=post, status='published',
        publish__year=year,
        publish__month=month,
        publish__day=day)
    comments = post.comments.filter(active=True)
    comment_form = CommentForm()
    new_comment = None
    if request.method == 'POST':
        comment_form = CommentForm(data=request.POST)
        if comment_form.is_valid():
            new_comment = comment_form.save(commit=False)
            new_comment.post = post
            new_comment.save()
    else:
        comment_form = CommentForm()
    post_tags_ids = post.tags.values_list('id', flat=True)
    similar_posts = Post.published.filter(tags__in=post_tags_ids)\
                                        .exclude(id=post.id)
    similar_posts = similar_posts.annotate(same_tags=Count('tags'))\
                                .order_by('-same_tags','-publish')[:4]
    
    return render(request, 
                    'blog/post/detail.html',
                    {'post' : post,
                    'comments': comments,
                    'new_comment':new_comment,
                    'comment_form': comment_form,
                    'similar_posts': similar_posts})
def post_share(request, post_id):
    post = get_object_or_404(Post, id=post_id, status='published')
    sent = False
    if request.method == 'POST':
            form = EmailPostForm(request.POST)
            if form.is_valid():
                cd = form.cleaned_data
                post_url = request.build_absolute_uri(post.get_absolute_url())
                subject = f"{cd['name']} recommends you read " \
                    f"{post.title}"

                message = f"Read {post.title} at {post_url}\n\n" \
                    f"{cd['name']}\'s comments: {cd['comments']}"

                send_mail(subject, message, '1353079083@qq.com',
                    [cd['to']])

            sent = True
    else:
            form = EmailPostForm()
    return render(request, 
                    'blog/post/share.html', 
                    {'post': post,
                    'form': form,
                    'sent': sent})
def post_search(request):
    form = SearchForm()
    query = None
    results = []
 # 如果请求中有query字段则获取表单中的数据进行处理
    if 'query' in request.GET:
 # 获取表单
        form = SearchForm(request.GET)
 # 如果表单中的数据验证通过，即有效，则获取并处理
        if form.is_valid():
 # 获取搜索内容保存下来
            query = form.cleaned_data['query']
 # 根据标题和正文字段构建搜索向量并生成搜索字段，再根据搜索内容筛选出匹配内容保存
            results = Post.published.annotate(
                search=SearchVector('title', 'body')
                ).filter(search=query)
 # 将搜索结果渲染到搜索模板并返回
    return render(request,
            'blog/post/search.html', {
            'form': form,
            'query': query,
            'results': results})

# Create your views here.
